import React from 'react'
import { BrowserRouter as Router, Route,Switch} from "react-router-dom"
function A() {
  return (
    <>
    组件A
    </>
  )
  
}
function B() {
  return (
    <>
    组件B
    </>
  )
  
}
function C() {
  return (
    <>
    组件C
    </>
  )
  
}
export default function App() {
  return (
    <Router>
      <Switch>
        <Route exact path='/a' component={A}>a</Route>
        <Route path='/b' component={B}>b</Route>
        <Route  path='/a/c' component={C}>c</Route>
        </Switch>
    </Router>
  )
}
